1. Field of Invention
This invention relates to radio frequency communication devices, systems, and program products. More particularly, this invention relates to an RFID system including a hybrid BackScatter-based RFID tag, system and method of operation protocol compatible with Bluetooth and/or IEEE 802.11x infrastructure.
2. Description of Prior Art
The automatic identification and data capture (AIDC) industry has recently begun to aggressively evaluate active RFID tags for applications now requiring enhanced security and improved efficiency for tracking and locating high-value assets in real-time. Emerging high performance active tag products operate within the 2.4 GHz Industrial, Scientific, and Medical (ISM) band while their passive counterparts have been proposed for operation within disjointed UHF bands that have not yet been harmonized across the world. Nevertheless, we do expect that eventually, most high performance passive RFID tag technologies will operate in the UHF frequencies from 862 MHz to 928 MHz across Europe and North America. Conversely, we also expect that active tag technologies will seek to become protocol compatible with low cost communication system standards that currently operate within the worldwide unlicensed 2.45 GHz ISM band. The 2.4 GHz frequency band is available throughout most parts of the world for low cost short-range wireless communications and has increased in popularity with the proliferation of networking and cordless technologies based on IEEE 802.11x and Bluetooth. A growing number of RFID systems have also been designed for operation within the 2.4 GHz-ISM frequency bands. Doing so leverages design synergies with other ISM band products and provides infrastructure added value, and reducing overall deployment costs. As more wireless technologies seek to use the 2.4 GHz band, co-existence and protocol compatibility issues have become even more pronounced. What is needed in the AIDC industry is an RFID tag, system and method of operation and system protocol compatible with Bluetooth and IEEE 802.11x and incorporating features of a mobile device.
Prior art related to RFID systems and devices includes:
1. U.S. Pat. No. 6,337,634 entitled “Radio Frequency Data Communication Device”, issued Jan. 8, 2002 describes a radio frequency identification device including an integrated circuit receiver, a transmitter, and a microprocessor. The receiver and transmitter together define an active transponder. The integrated circuit is preferably a monolithic single die integrated circuit including the receiver, the transmitter, and the microprocessor. The transmitter has a plurality of transmitting circuits, the plurality of transmitting circuits configured to selectively realize a plurality of modulated backscatter schemes. The integrated circuit is configured to receive and apply radio frequency signals via an antenna, the antenna and tunable circuitry cooperating in operation by switching the transmitting circuits with respect to the antenna to enable one of the transmitting circuits to realize one of the modulation schemes. Because the device includes an active transponder, instead of a transponder which relies on magnetic coupling for power, the device has a much greater range.
2. U.S. Pat. No. 5,790,946, entitled “Wakeup Device for Communication System”, issued Aug. 4, 1998 describes a wake communication system including a first communication device for receiving data and a wake up signal. Operation of the first communication device includes an active mode of operation and a sleep mode of operation for reducing power consumption. Further, the system includes a switch for switching the first communication device to and from sleep mode in response to receiving the wake up signal. The system also includes a second communication device for transmitting data to the first device during its active mode, and for transmitting the wake up signal to the first device during its sleep mode.
3. U.S. Pat. No. 6,078,251, entitled “Integrated Multi-Meter and Wireless Communication Link”, issued Jun. 20, 2000 describes an apparatus for object identification including a multi-meter terminal having a plurality of data modules, a triggering device for initiating one of the plurality of data modules to retrieve object identification data from an object. A radio module downloads the retrieved object identification data to a host and a housing contains the data modules, triggering device and the radio module. An RFID interrogator processes multiple tag protocols. The triggering device is responsive to a triggering signal from the host. The multi-meter terminal further includes a user interface and wherein the triggering device is responsive to a triggering signal initiated by the user through the user interface or generated by one of the plurality of data modules or generated manually by a user.
None of the prior art discloses an RFID system including a hybrid backscatter-based REID tag protocol compatible with low power communication systems using Bluetooth and/or IEEE 802.11x infrastructure.